Booking return leg of journey using BA Companion Voucher
So I have just booked a flight for April 2021 one way to secure the companion voucher seats. In normal circumstances booking the return leg is easy as you just call the call centre when flights are available and they add it to your companion voucher, however currently I can't get through to the call centre!! Any ideas on how to resolve this as we potentially will miss getting our return tickets but surely lots of other people are in this predicament?